AP Biosciences Doses First Patient in Phase 1/2 Clinical Trials of AP402 for HER2+ Cancer Patients

TAIPEI, Taiwan, April 22, 2025 (GLOBE NEWSWIRE) -- AP Biosciences, a clinical-stage biopharmaceutical company dedicated to transforming cancer therapy through development of innovative bispecific antibodies, today announced that it has dosed the first patient in its Phase 1 study evaluating AP402, a potential first-in-class, next generation T cell engager targeting CD137 and p95HER2 in patients relapsed/refractory to anti-HER2 treatment. The Phase 1 clinical trial, currently taking place in Australia, is designed to evaluate the safety, tolerability, and preliminary efficacy of AP402 in HER2+ patients with advanced solid tumors, including breast cancer. The following dose expansion phase of the study may include clinical sites in Taiwan, South Korea and the United States.

“AP402 targets p95HER2, a truncated form of HER2 present in 30-40% of HER2-positive cancers, which is associated with exceptionally poor prognosis, and not addressable by conventional anti-HER2 therapies,” said Dr. Jeng Her, Ph.D., Founder and Chief Executive Officer of AP Biosciences. “AP402 represents the only T-cell engager in human trials which bridges activated T cells and p95HER2-expressing cancer cells in the tumor – a differentiated mechanism that could deliver a powerful immune response while minimizing systemic toxicity. AP402 thus offers promise as a potential therapeutic option for patients with difficult-to-treat cancers that could enhance efficacy and safety where other treatments fall short.”

AP402-101 (NCT06669975), is a multi-center, open-label Phase 1 trial, enrolling up to 85 patients divided in two parts: a dose-escalation phase to determine the maximum tolerated dose and recommended Phase 2 dose (RP2D), followed by a dose-expansion phase targeting specific HER2-positive tumor types. Primary endpoints of the study include safety and tolerability, while secondary endpoints will evaluate objective response rate (ORR), disease control rate (DCR), and pharmacokinetic (PK) parameters. Exploratory endpoints will assess pharmacodynamic biomarkers and immunogenicity.

The Company has announced that preclinical data supporting the therapeutic potential of AP402 will be presented in a poster at this year’s American Association of Cancer Research (AACR) conference.

Visit https://www.apbioinc.com/en/ for more information about AP Biosciences and its pipeline of next-generation cancer therapies.

About AP402
AP402 is a first-in-class bispecific antibody originated and developed by AP Biosciences to target p95HER2, a truncated variant of HER2 that is expressed in 30-40% of treatment-resistant HER2-positive cancers. AP402 is constructed using T-cube bispecific antibody technology which combines p95HER2 targeting with a CD137 activation domain to enable target-dependent T-cell activation exclusively in the tumor microenvironment. The antibody design facilitates clustering of HER2 variants to effectively trigger CD137-mediated T-cell activation, while minimizing potential side effects related to systemic cytokine release. The binding domains for p95HER2 and CD137 are designed to enhance bridging between HER2 variant-expressing cancer cells and CD137-expressing T-cells, ensuring efficient immune cell recruitment without spatial hindrance. This novel mechanism has positioned AP402 as a promising potential therapeutic approach to addressing tumors that have developed resistance to traditional anti-HER2 therapies, offering new hope for patients with refractory/recurrent cancers.

About AP Biosciences
AP Biosciences is a Taiwan-based clinical-stage biopharmaceutical company committed to developing innovative antibody-based therapies for cancer and other diseases. Applying its proprietary Omni-Mab and T-cube platforms, AP Biosciences is pioneering next generation bispecific antibodies that activate the immune system precisely where it’s needed, for both established and treatment-resistant cancers.

AP Biosciences Contact
Spike Lo
AP Biosciences
pr@apbioinc.com
+886-2-2653-2886

Media Contact
Jason Braco, PhD
LifeSci Communications
jbraco@lifescicomms.com
(908)-432-4243


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